When an optical inspection is generally performed on an object to be inspected, an image device of a device of optical inspection requires a complicated operation in order to minimize an inspection error of a surface of shape formed with a curved surface. To be a reference for a complicated operation, is an image captured angle of the image device which corresponds to an incident angle and a reflected angle of light source with a normal line of the curved surface and a distance between a lens of the image device and the curved surface.
When the object to be inspected is a plane, an optical inspection may be performed while constantly maintaining the initially determined image captured angle of the image device and the distance between the lens and the surface of the image device. However, when the object to be inspected is a curved surface, the distance between the lens of the image device and the surface and the direction of the normal line of the curved surface are persistently changed depending on the test position. Therefore, in the inspection for a curved surface, it is important to constantly maintain the image captured angle of the image device for the normal line of a curve surface and the distance between the lens and the surface of the image device.
CFRP is an abbreviation of Carbon Fiber Reinforced Plastics, and a carbon fiber reinforced plastics (CFRP) material is a composite material made of a plurality of carbon fiber and a plurality of thermosetting resin. Since various shapes of products may be produced due to a property of carbon fiber reinforced plastics (CFRP) material, products made of the carbon fiber reinforced plastics (CFRP) may comprise a shape composed of a curved surface of which a curved ratio is large. Also, it has been increased that the carbon fiber reinforced plastics (CFRP) material is used for a large size product.
Therefore, the device of optical inspection is required to perform a precise inspection for a surface of which a curved ratio is large, while it is required to perform a high speed inspection for a large sized surface.